As an update, I wanted to say that I decided not to drain the pool even though it may have been an easier process. We had gotten this small pool as an experiment and thought it would give us a chance to learn. And learn, we did! We read everything we could find on the forum and the pool is now a sparkling blue. In addition to ridding the pool of the algae, I have included some DE to our sand filter and indeed it does add a pleasing sparkle!

To try to deal with the continuing problems with high PH and high alkalinity, I've just gone through the process of adding borates as per the instructions for adding Borax. I am in the phase of waiting for 48 hours before testing the borate level (and once again, trying to bring down the high PH level). I am hoping this will be an added "inoculation" against algae and the PH pendulum.

Thank you for all the wonderful information!